Threading device for sewing machines



March 14, 1967 YOSHIHIKO NAKAJIMA ,3 8

THREADING DEVICE FOR SEWING MACHINES Filed Feb. 24, 1964 2 Sheets-Sheet l INVENTOR.

amh 1967 YOSHlHlKO NAKAJIMA 3,303,778

THREADING DEVICE FOR SEWING MACHINES I 2 Sheets-Sheet 2 Filed Feb. 24, 1964 INVENTOR.

United States Patent Office 3,308,778 Patented Mar. 14, 1967 THREADING DEVICE FOR SEWING MACHINES Yoshihiko Nakajima, Suginami-ku, Tokyo, Japan, asslgnor to Janome Sewing Machine Co., Ltd., Tokyo, Japan Filed Feb. 24, 1964, Ser. No. 346,672 Claims priority, application Japan, Feb. 27, 1963, 38/ 12,132 16 Claims. (Cl. 112-225) The present invention relates to a threading device for sewing machines, and more particularly to a threadmgdevice which is permanently attached to a sewing machine.

Threading devices according to the known art require the alignment of a threading means, such as a hook or wire loop with theneedle eye. While the threading of the threading means through the needle eye is easier than the threading of the thread, a certain skill is nevertheless required of the operator.

It is one object of the invention to provide a threading device in which the threading means, such as a hook, is guided on the needle to insert the hook into the needle eye. 7

Another object of the invention is to mount a threading device on a sewing machine in such a manner that it can be shifted between an inoperative position out of the way of sewing operations, and a threading position in which it can be operated to insert a threading means into the needle eye.

Another object of the invention is to mount the threading means in such a manner on the sewing machine that it can be turned between a retracted position and a threading position, and shifted in the threading position in axial direction of the turning movement to insert a threading means into the needle eye, and to withdraw the threading means with the thread from the needle eye.

Another object of the invention is to mount a threading means on a sewing machine in such a manner that it is automatically returned by spring means to a retracted position after a threading operation has been performed.

It is the principal object of the invention to provide a sewing machine with a small and compact threading device which does not disturb sewing operations, and which can be easily operated by an unskilled person to thread a yarn into the eye of the needle.

It is another object of the invention to mount a threading device on the presser bar of a sewing machine in a position closely adjacent the needle to be threaded so that the dimensions of the threading device can be made very small.

With these objects in view, a threading device according to the present invention comprises a threading means, such as a hook, and positioning means which cooperate with the needle to guide the threading means toward and through the needle eye. In the preferred embodiment of the invention, the positioning means include two guide portions defining with each other a recess, and located on opposite sides of the needle shank while the threading means is guided toward the center of the needle eye.

The threading device is preferably mounted on the presser bar of a sewing machine at such a level that the threading means is located at the level of the needle eye when the needle is retracted to its upper end position.

The threading device includes a support for the threading hook and for the positioning means, and this support is mounted on the presser bar for angular movement between a higher retracted position and a lower threading position, and is axially shiftable in the lower threading position between a position in which the threading hook is spaced from the needle, and a position in which the threading hook passes through the needle eye while the guide portions of the positioning means are located on opposite sides of the needle shank. A pin passing through a bore of the presser bar mounts the threading device on the needle bar, and a coil spring surrounding the pin is torsionally stressed to urge the threading device to turn to the retracted position, and also to move away from the needle. A finger-engaging piece is controlled by the operator during the threading operation, and when the finger-engaging piece is released, the spring returns the threading device automatically to its retracted position out of the way of sewing operations.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating a portion of a sewing machine provided with a threading device according to the invention;

FIG. 2 is a perspective view corresponding to FIG. 1, and illustrating the threading device in operation;

FIG. 3 is an exploded perspective view of the parts of the threading device;

FIG. 4 is a perspective view illustrating the threading device in a retracted position;

FIG. 5 is a fragmentary side view illustrating a detail of the threading device on an enlarged scale;

FIG. 6 is a plan view, partially in section, of the threading device shown in FIG. 5

FIG. 7 is a front View of the lower part of a sewing machine with the threading device of the invention in the retracted position; and

FIG. 8 is a side view corresponding to FIG. 7 and illustrating the threading device in a threading position.

Referring now to the drawings, on the downwardly projecting portion 22 of the casing of a sewing machine, a needle bar 1 and a presser bar 5 are mounted. A needle 3 is attached to the lower end of the needle bar of the part 1 by clamping means 2 including a screw, and has at the lower end thereof a needle eye 4. A presser foot 8 is attached to presser bar 5 by a clamping means 7. The upper part of the presser bar 5 has a depressed smooth and flat face portion 6 facing toward the needle and needle bar.

A pin 10 is fixedly secured to a band-shaped support 9, and passes through a bore 25 in the region of face 6 of presser bar 5. A finger-engaging knob 11 is secured to the end of pin 10 and has a small hole into which one end of a coil spring 12 is inserted, the other end of the coil spring being hooked onto the presser bar 5. When pressure is exerted on finger-piece 11, pin 10 and support 9 are shifted in axial direction of the pin from the position shown in FIG. 1 to the position shown in FIG. 2 while the coil spring is compressed.

In the position of FIGS. 1 and 2, coil spring 12 is also torsionally stressed so that the spring will urge support 9 with knob 11 and pin 10 to turn to the higher retracted position shown in FIGS. 4 and 7. Support 9 is a bent plate whose lower portion has two threaded bores, as best seen in FIG. 3. A positioning means 13 is secured to support 9 by a screw 19 engaging the upper port 9, and a threading means 26 is secured to support 9 by screw 20 engaging the lower threaded bore in sup-.

port 9.

Positioning means 13 has a flat mounting portion, and a pair of guide members 15 and 16 which define between each other an elongated slot which is best seen in FIG. 6. Guide portions 15 and 16 are horizontal rectangular plates, guide portion 16 being shorter than guide portion Threading means 26 includes a rectangular mounting threaded bore in supv plate with a slot through which screw 20 passes. Positioning means 13 has a similar slot so that the positions of threading means 26 and positioning means 13 can be adjusted in vertical direction.

Threadingmeans 26 includes a shank portion 17 having a hook 18 at its end, asbest seen in FIGS. 5 and 6.

The threading means is adjusted on support 9 until the hook 18 and its shank 17 are located at the level of the needle eye 3a when the needle bar and the needle are in V the retracted upper end position shown in FIGS. 1 and 2.

turn pin 10 with support 9, positioning means 13 and threading means 26 to the retracted position shown in FIGS. 4 and 7 until support 9 abuts abutment 23. This is the normal inoperative position of the threading device in which sewing operations are performed. Since the projecting parts 15, 16 and 17 are located in recess 22a, they do not interfere with the hands of the operator, with the fabric, or with the thread.

Assuming that it is desired to insert a new thread into the eye of the needle, the machine is first operated so that needle bar 1 and needle 3 are moved to the upper end position in which the needle eye is located at the highest level.

The operator grips knob 11, and turns the same against the action of coil spring .12 until the longer guide member 15 abuts one sideof needle 3. The other guide member 16 is shorter, so that it passes the needle during the clockwise turning movement of the threading device. 'Consequently, the threading device 9, 13, 26 is stopped in a position in which the recess between guide portions '15 and 16 is aligned with the needle. Due to the previous adjustment of threading means 26 on sup-port 9 by means of screw and the corresponding slot in threading means 26, the hook 18 is located exactly at the level of the needle eye 4.

When the threading device is in this threading position, the operator presses against knob 11 in axial direction so that spring 10 is longitudinally compressed and the threading device moves from the inoperative position shown in FIG. 1 to the operative position shown in FIG. 2. During such movement, the inner edges of guide portions 15 and 16 define the position of the threading device in relation to the needle 3 so that the-threading means 17 and 18 which is located in the vertical plane of symmetry of the guide recess between guide members 15 and 16, is precisely aligned with needle eye 4 and enters the same. In the operative position shown in FIGS. 2, 5 and 6, a thread 18a is inserted into the hook, and when the operator permits spring 12 to withdraw the threading device in axial direction of pin 10, thread 18a is pulled by hook 18 through eye 4 of needle 3. Atthe same time,

guide portions 15 and 16 move to the left as viewed in FIG. 6, and when the. end of guide portion 16 has passed needle 3, spring 12 urges the threading device to turn'in counterclockwise direction until support 9 abuts the abutrnent 23 in recess 22a of the sewing machine casing.

It will be seen that the threading device of the invention accomplishes the insertion of a thread into the needle eye in an extremely easy and foolproof operation, since the threading means 17, 18 is automatically aligned in vertical and horizontal planes with the needle eye so that no skill of the operator is required for the threading operation. v

This is due to the fact that the height of the threading means is determined by the relationship between the pressed bar and the needle bar in the upper end position of the'latte'r, and that the alignment in a horizontal plane is automatically achieved by the guide portions 15 and 16.

Due to the fact that the threading device is mounted on the presser bar 5, the threading device is located in close proximity to the needle when turned to the threading position so that only a very short horizontal shifting movement is required for inserting the threading hook'17, 18 into the needle eye, resulting in very short guide portions 15 and 16, and in a short threading hook 17 and 18.

The small dimensions of these portions have the advantage that the threading device does not disturb the normal sewing operations, particularly if the projecting parts thereof are located in the recess 22a in the retracted position of the threading device. Of course, the short length of the threading hook also reduces the time required for insertion of the threading hook into the eye, and for retraction of the threading hook with the thread.

The use of a single spring 12 for performing two functions, namely the retraction of the threading means from the eye, and the turning of the entire'threading device to the retracted position of rest, further assures the simplicity of the device which results in low manufacturing cost and compact construction as is desired for a threading device which is mounted on a sewing machine.

It will be understood that each of the elements'described above, or two or more together, may also find a useful application in other types of threading devices diifering from the types described above.

While the invention has been illustrated and described as embodied in a threading devicernounted on the presser bar of a sewing machine and being movable between a retracted position and a position in which a threading hook is precisely aligned with a needle eye, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist'of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the stand point of prior art, "fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a sewing machine, in combination, a needle bar, a needle having an eye and mounted on said needle bar; a presser ba'r located opposite said needle bar and needle and formed with a bore perpendicular to said needle; a support; mounting means for mounting said support on said presser bar for movement between a higher retracted position and a lower position, and also for movement in I said lower position between an inoperative position farther spaced from said needle and an inoperative position closer to said needle, said mounting means including a pin passing through said bore of said presser bar and being turnable therein for moving said support between the higher and lower positions, and being axially shiftable therein for moving said support between said inoperative and operative positions; spring means secured to saidpin and to said presser bar and urging said support to turn to said higher position and to move to said inoperative position;

threading means carried by said support and being spaced from said needle in said retracted and inoperative position; positioning means carried by said support and being spaced from said needle in said retracted position, said positioning means cooperating with said needle during movement of said support from said inoperative position to said operative position to align said threading means with said needle eye whereby said threading means enters said needle eye and projectsthrough the same in said op erative position adopted to draw a thread through said needle eye during movement of said support to said inoperative position.

2. In a sewing machine, in combination, a needle bar, a needle having an eye and mounted on said needle bar; a presser bar located opposite said needle bar and needle and formed with a bore perpendicular to said needle; a support; mounting means for mounting said support on said presser bar for movement between a higher retracted position and a lower position, and also for movement in said lower position between an inoperative position farther spaced from said needle and an operative position closer to said needle, said mounting means including a pin passing through said bore of said presser bar and being turn able therefor for moving said support between the higherand lower positions, and being axially shiftable therein for moving said support between said inoperative and operative positions; a finger-engaging piece secured to said pin on the side of said presser bar remote from said support, and adapted to be manually operated for moving said support between said positions thereof; a coil spring surrounding said pin and located between said fingeren-gaging piece and said presser bar secured to the same and urging said support to turn to said higher position and to move to said inoperative position; threading means carried by said support and being spaced from said needle in said retracted and inoperative positions; positioning means carried by said support and being spaced from said needle in said retracted position, said positioning means cooperating with said needle during movement of said support from said inoperative position to said operative position to align said threading means with said needle eye whereby said threading means enters said needle eye and projects through the same in said operative position adapted to draw a thread through said needle eye during movement of said support to said inoperative position.

3. In a sewing machine, in combination, a needle bar, a needle having an eye and mounted on said needle bar; a presser bar located opposite said needle bar and needle; a support; mounting means for mounting said support on said presser bar for angular movement between a higher retracted position and a lower position substantially aligned with said needle bar, and also for horizontal movement in said lower position between an inoperative position farther spaced from said needle and an operative position closer to said needle; threading means carried by said support and being spaced from said needle in said retracted and inoperative positions; positioning means carried by said support and being spaced from said needle in said retracted position, said positioning means including a pair of guide portions located on opposite sides and equally spaced from said threading means above the same, the guide portion trailing in the direction of angular movement toward said threading position being longer than the leading guide portion and abutting said needle in said inoperative position, said guide portions defining a recess adapted to receive said needle during movement of said support from said inoperative position to said operative position so that said guide portions align said threading means with said needle eye whereby said threading means enters said needle eye and projects through the same in said operative position adapted to draw a thread inserted into said threading means through said needle eye during movement of said support to said inoperative position.

4. In a sewing machine, in combination, a needle bar, a needle having an eye and mounted on said needle bar, said needle bar and needle being movable between an upper end position and a lower end position; a presser bar located opposite said needle bar and needle; a support; mounting means for mounting said support on said presser bar for angular movement between a higher retracted position and a lower position substantially aligned with said needle bar, and also for horizontal movement in said lower position between an inoperative position farther spaced from said needle and an operative position closer to said needle; threading means carried by said support and being spaced from said needle in said retracted and inoperative positions, said threading means being located at the level of said needle eye in said upper end position of the same when said support is in said lower position; positioning means carried by said support and being spaced from said needle in said retracted position, said positioning means being located at a higher level than said threading means and including a pair of guide portions located on opposite sides and equally spaced from said threading means above the same, the guide portion trailing in the direction of angular movement toward said threading position being longer than the leading guide portion and abutting said needle in said inoperative position, said guide portions defining a recess adapted to receive said needle during movement of said support from said inoperative position to said operative position so that said portions align said threading means with said needle eye whereby said threading means enters said needle eye and projects through the same in said operative position adapted to draw a thread inserted into said threading means through said needle eye during movement of said support to said inoperative position.

5. In a sewing machine including a needle having a needle eye, and a member located opposite said needle, in combination, a threading device, mounting means for mounting said threading device on said member for turning movement between a retracted position and a threading position located in the proximity of said needle, and for also mounting said threading device in said threading position for rectilinear movement in a direction perpendicular to said needle between an inoperative position and an operative position, said threading device including a threading means spaced from said needle in said inoperative position, spring means secured to said threading device and to said member and being torsionally stressed in said threading position, and compressed in said operative position to urge said threading device to move to said inoperative and retracted positions, and positioning means cooperating with said needle during movement of said threading device from said inoperative position to said operative position to align said threading means with the needle eye whereby said threading means enters the needle eye and projects through the same in said operative position.

6. In a sewing machine including a needle having a needle eye, a body portion having an abutment, and a pressure member located opposite said needle, in combination, a threading device, mounting means for mounting said threading device on said member for turning movement between a retracted position abutting said abutment and a threading position located in the proximity of said needle, and for also mounting said threading device in said threading position for rectilinear movement in a direction perpendicular to said needle between an inoperative position and an operative position, said threading device including a threading means spaced from said needle in said inoperative position, spring means secured to said threading device and to said member and being torsionally stressed in said threading position, and compressed in said operative position to urge said threading device to move to said inoperative and retracted positions so as to abut said abutment, and positioning means cooperating with said needle during movement of said threading device from said inoperative position to said operative position to align said threading means with the needle eye whereby said threading means enters the needle eye and projects through the same in said operative position.

7. An arrangement as set forth in claim 6 wherein said body portion has a low portion formed with a recess having said abutment, and wherein said positioning means and threading means are located in said recess in said retracted position.

8. In a sewing machine including a needle having a needle eye located in a vertical plane; a threading device having a threading means, and a positioning means having a guide means, said threading means and said guide means extending perpendicularly to said'plane; mounting means for mounting said threading device on said sewing machine for turning movement about an axis per-' pendicular to said plane between a retracted position and a threading position, and also for rectilinear movement in said threading position in the direction of said axis between an inoperative position in which said threading means is spaced from said eye, and an operative position in which said threading means is located in said eye, said positioning means turning with said threading device about said axis and said guide means abutting said needle in said threading position for guiding said threading device during said rectilinear movement from said inoperative to said operative position; spring means biasing said threading device to move from said threading position to said retracted position, and from said operative position to said inoperative position; and a manually operable 'member for moving said threading device to said threading and operative positions whereby said threading means is first aligned with said needle eye in said threading and inoperative positions, and then moved through said needle eye to said operative position,

9. Apparatus according to claim 8 wherein said sewing machine includes a presser bar; and wherein said mounting means mount said threading device on said presser bar.

10. An arrangement according to claim 9 wherein said presser bar has a bore; wherein said mounting means include a pin passing through said bore of said presser bar and being slidable and turnable in said-bore for supporting said threading device for, turning and rectilinear movement; and wherein said manually operable member is secured to said pin.

11. An arrangement according to claim 9 wherein said threading device is located forwardly of said presser bar; and wherein said manually operable member is located rearwardly of said presser bar.

12. An arrangement according to claim 11 and including a springvsurrounding said pin between said presser bar and said manually operable member and being torsionally stressed in said threading position and longitudinally stressed in said operative position to urge said threading device to move to said inoperative and retiacted positions.

13. An arrangement according to claim 8 wherein said spring means has one end secured to said manually operable member and to said threading device and the other end secured to said sewing machine so as to be torsionally stressed in said threading position and longitudinally stressed in said operative position to urge sad threading device to move to said inoperative and retracted positions.

14. In a sewing machine including a needle having a needle eye, said needle having a retracted position, and a presser member located opposite said needle in a vertical plane passing through the same and having a normal retracted position, in combination, a threading device; mounting means for mounting said threading device on said presser member for turning movement about an axis perpendicular to said needle and located in said plane, between a retracted position and a threading position located in said plane in the proximity of said needle, and for also mounting said threading device in said threading positionfor rectilinear movement in the direction of said axis and perpendicular to said needle between an inoperative position and an operative position, said threading device including a threading means axially spaced from said needle. in said inoperative position and projecting through said needle eye in said operative position; spring means biasing said threading device to move from said threading position to said retracted position, and from said operative position to said inoperative position; positioning means secured to said threading device and moving along a circular path during movement of said threading device in said inoperative position from said retracted to said threading position and abutting said needle in said threading position so as to stop said threading device, said positioning means having a guide means extending paralel to said axis for guiding said threading device from said inoperative position to said operative position; and a manually operable member for moving said threading device to said threading and operative positions whereby said threading means is first aligned with the needle eye in said thread ing position and then moved through the same to said operative position.

15. In a sewing machine including a needle having a needle eye, said needle having a retracted position, and a presser member located opposite said needle in a vertical plane passing through the same and having a normal retracted position, in combination, a threading device; mounting means including a pin pas-sing through said presser member for mounting said threading device on said presser member for turning movement about an axis prependicular to said needle located in said plane, between a retracted position and a threading position located in said plane in the proximityof said needle, and for also mounting said threading device in said threading position for rectilinear movement in the direction of said axis and perpendicular to said needle between an inoperative position and an operative position, said threading device including a threading means axially spaced from said needle in said inoperative position and projecting through said needle eye in said operative position; spring means biasing said threading device to move from said threading position to said retracted position, and from said operative position to said inoperative position; positioning means secured to' said threading device and moving along a circular path during movement of said threading device in said inoperative position from said retracted to said threading position and abutting saidneedle in said threading position so as to stop said threadmeans extending parallel tosaid axis for guiding said threading device from said inoperative position to said operative position; and a manually operable member secured to said pin for turning and axially moving the same for moving said threading device to said threading and operative positions whereby said threading means is first aligned with the needle eye in said threading position and then moved through the same to said operative position.

16. In a sewing machine including a needle having a needle eye, said needle having a retracted position, and a presser member located opposite said needle in a vertical plane passing through the same and having a normal retracted position, in combination, a threading device; mounting means including a pin passing through said presser member for mounting said threading device on said presser member for turning movement about an axis perpendicular to said needle located in said plane, between a retracted position and a threading position located in said plane in the proximity of said needle, and for also mounting said threading device in said threading position for rectilinear movement in the direction of said axis and perpendicular to said needle between an inoperative position and an operative position, said threading device including a threading means axially spaced from said needle in said inoperative position and projecting through said needle eye in said operative position; a spring means secured to said threading device and to said presser member and being torsionally stressed in said threading positions and being longitudinally stressed in said operative position to urge said threading device to move to said inoperative and'retracted positions; positioning means secured to said threading device and moving along a circular path during movement of said thread- 9 1% ing device in said inoperative position from said retracted References Cited by the Examiner to said threading position and abutting said needle in said UNITED STATES PATENTS threading position so as to stop said threading device, said positioning means having a guide means extending 1,100,763 6/1914 Naylor 112*255 parallel to said axis for guiding said threading de- 5 1,260,611 3/ 1913 Welling 112225 vice from said inoperative position to said operative posi- 2,655,336 10/ 1953 g tion; and a manually operable member secured to said pin 2,680,418 6/ 1954 Ullisperger 112225 for turning and axially moving the same for moving said threading device to said threading and operative position CK LAWSON, Primary Examiner. whereby said threading means is first aligned With the 10 JORDAN FRANKLIN, GUEST,

needle eye in said threading position and then moved Assistant Emminers through the same to said operative position. 

1. IN A SEWING MACHINE, IN COMBINATION, A NEEDLE BAR, A NEEDLE HAVING AN EYE AND MOUNTED ON SAID NEEDLE BAR; A PRESSER BAR LOCATED OPPOSITE SAID NEEDLE BAR AND NEEDLE AND FORMED WITH A BORE PERPENDICULAR TO SAID NEEDLE; A SUPPORT; MOUNTING MEANS FOR MOUNTING SAID SUPPORT ON SAID PRESSER BAR FOR MOVEMENT BETWEEN A HIGHER RETRACTED POSITION AND A LOWER POSITION, AND ALSO FOR MOVEMENT IN SAID LOWER POSITION BETWEEN AN INOPERATIVE POSITION FARTHER SPACED FROM SAID NEEDLE AND AN INOPERATIVE POSITION CLOSER TO SAID NEEDLE, SAID MOUNTING MEANS INCLUDING A PIN PASSING THROUGH SAID BORE OF SAID PRESSER BAR AND BEING TURNABLE THEREIN FOR MOVING SAID SUPPORT BETWEEN THE HIGHER AND LOWER POSITIONS, AND BEING AXIALLY SHIFTABLE THEREIN FOR MOVING SAID SUPPORT BETWEEN SAID INOPERATIVE AND OPERATIVE POSITIONS; SPRING MEANS SECURED TO SAID PIN AND TO SAID PRESSER BAR AND URGING SAID SUPPORT TO TURN TO SAID HIGHER POSITION AND TO MOVE TO SAID INOPERATIVE POSITION; THREADING MEANS CARRIED BY SAID SUPPORT AND BEING SPACED FROM SAID NEEDLE IN SAID RETRACTED AND INOPERATIVE POSITION; POSITIONING MEANS CARRIED BY SAID SUPPORT AND BEING SPACED FROM SAID NEEDLE IN SAID RETRACTED POSITION, SAID POSITIONING MEANS COOPERATING WITH SAID NEEDLE DURING MOVEMENT OF SAID SUPPORT FROM SAID INOPERATIVE POSITION TO SAID OPERATIVE POSITION TO ALIGN SAID THREADING MEANS WITH SAID NEEDLE EYE WHEREBY SAID THREADING MEANS ENTERS SAID NEEDLE EYE AND PROJECTS THROUGH THE SAME IN SAID OPERATIVE POSITION ADOPTED TO DRAW A THREAD THROUGH SAID NEEDLE EYE DURING MOVEMENT OF SAID SUPPORT TO SAID INOPERATIVE POSITION. 